Solid Phase Sciences Corporation (SPSC) proposes to produce a combinatorial library of substituted acridine and pyridine based analogs for anti-cancer screening. The library will consist of 5 milligrams each of a total of 640 individual compounds. SPSC will accomplish this by utilizing it's novel high-loading paramagnetic support and a newly developed automated reaction plenum. Specifically, libraries will be made off of this high- loading support to separate the desired products from the soluble components of the reaction mixture. A follow-up structure-activity- relationship (SAR) library composed of 50-100 compounds will also be produced based on the screening results of the 640 compound library. The goal of the Phase II effort will be to complete the development of the new automated reaction plenum while producing a library composed of a series of acridine and pyridine based heterocyclic compounds for anti cancer screening at the National Cancer Institute. PROPOSED COMMERCIAL APPLICATION: A commercial automated combinatorial library synthesizer for drug discovery.